Power steering shudder

I recently replaced ball joints, and after getting everything back together I noticed a shudder in the steering wheel when turning at low speed or stopped. I added type F to cold level (at cold) which made it a bit better, but the issue has come back and fluid level has not dropped any measurable amount. Should I be worried about the rack going bad? I've never had any symptoms like this before I replaced the ball joints, so I'm wondering if I could have damaged something while doing that repair. Alignment, by eyeball standards, is good, and it has been aligned somewhat recently. I'm pretty sure I heard something about a slack adjustment for the steering rack, how is that done and could that help?

Has anyone had these symptoms? I'm pretty worried about this one, because I can't afford a new or rebuild rack right now, or a pump, or anything really, and I've put a whole lot of money in this car that I won't get back anyway. Part of me wants to just sell it and get something newer/in better shape, but I can't afford to do that either. Any information on this issue and how to make it (inexpensively) go away would be great. Would slightly overfilling the ps reservoir be bad? Since the one time I filled it it seemed to help, maybe it just isn't purged all the way? All help would be appreciated.
Alex

I have experienced a shuddering issue when performing sharp turns at low speeds. However, I did not have any shuddering when turning while the vehicle was stopped. My problem was an alignment issue (toe in was set improperly). Having an alignment done corrected this problem for me.

I think the rack is bad. There is a clunk when turning the steering wheel with the engine off and there isn't any play in the tie rods. I'm going to pick-a-part tomorrow to get at least one rack and maybe a p/s pump and lines.

What all models are compatible for swapping with the '91 240 with a Cam rack? Are any of the manual racks, early 240, or 740/940 model racks compatible?

Also, are there any tips or tricks to removing the racks quickly? I'm leaving from class to go to Pic-a-part yard in Indy, and I may only have a few hours before it closes. Any help is appreciated.

I pulled a steering rack from a late 80s 240 wagon, and I'm currently in the process of installing it. What's hanging me up, however, is getting the steering shaft into the coupler/u joint. How do I do this? When I pulled the rack from the parts car I pulled the whole steering shaft because the shaft wouldn't separate from the lower coupler, isn't it okay to just install the shaft into the upper coupler on my car? Hopefully some of you have some insight into getting the shaft into the coupler, it's only gone in a few millimeters, not nearly enough.

Did you pull the power steering belt off at some point? I have found that my 1990 240DL is real temperamental about how much tension is on the power steering belt. Too much or too little tension will cause a shudder.

I did mess around with the tension of the belt quite a bit, but we have switched lanes. The steering rack's play is the suspected culprit now and I need to get the new one on the steering shaft, does anyone know how to do this? Maybe I'll just create a new thread, didn't want to, but the shudder isn't my 1st priority anymore as it will probably be fixed with this rack.

If you're still having shuddering after replacing the rack, make sure the front tires are fully inflated. Under-inflated tires cause the rack to be strained when turning at low speeds. I've had this problem with a 740 and a 960. Adding Lucas to the power steering fluid helps also.